package cn.util;

import org.apache.commons.lang.StringUtils;
import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;

import javax.crypto.Cipher;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;
import javax.crypto.spec.IvParameterSpec;
import java.security.Key;
import java.security.spec.AlgorithmParameterSpec;

/**
 * 加密/解密工具
 *
 * @date 2017年4月18日 上午11:27:36
 */
public class EncryptUtil {

	private final byte[] DESIV = new byte[] { 0x12, 0x34, 0x56, 120, (byte) 0x90, (byte) 0xab, (byte) 0xcd, (byte) 0xef };// 向量

	private static AlgorithmParameterSpec iv = null;// 加密算法的参数接口
	private static Key key = null;
	//加密解密 秘钥
	private static 	String  deSkey = "codepaymiyao!@#$%^&**()";// 自定义密钥

	private static String charset = "utf-8";

	/**
	 * 初始化
	 * @param deSkey	密钥
	 * @throws Exception
	 */
	public EncryptUtil(String deSkey, String charset) throws Exception {
		if (StringUtils.isNotBlank(charset)) {
			this.charset = charset;
		}
		DESKeySpec keySpec = new DESKeySpec(deSkey.getBytes(this.charset));// 设置密钥参数
		iv = new IvParameterSpec(DESIV);// 设置向量
		SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");// 获得密钥工厂
		key = keyFactory.generateSecret(keySpec);// 得到密钥对象
	}

	/**
	 * 加密
	 * @author ershuai
	 * @date 2017年4月19日 上午9:40:53
	 * @param data
	 * @return
	 * @throws Exception
	 */
	public static String encode(String data) throws Exception {
		new EncryptUtil(deSkey,"utf-8");
		Cipher enCipher = Cipher.getInstance("DES/CBC/PKCS5Padding");// 得到加密对象Cipher
		enCipher.init(Cipher.ENCRYPT_MODE, key, iv);// 设置工作模式为加密模式，给出密钥和向量
		byte[] pasByte = enCipher.doFinal(data.getBytes("utf-8"));
		BASE64Encoder base64Encoder = new BASE64Encoder();
		return base64Encoder.encode(pasByte);
	}

	/**
	 * 解密
	 * @author ershuai
	 * @date 2017年4月19日 上午9:41:01
	 * @param data
	 * @return
	 * @throws Exception
	 */
	public  static String decode(String data) throws Exception {
		new EncryptUtil(deSkey,"utf-8");
		Cipher deCipher = Cipher.getInstance("DES/CBC/PKCS5Padding");
		deCipher.init(Cipher.DECRYPT_MODE, key, iv);
		BASE64Decoder base64Decoder = new BASE64Decoder();
		byte[] pasByte = deCipher.doFinal(base64Decoder.decodeBuffer(data));
		return new String(pasByte, "UTF-8");
	}

}